This invention relates to window assemblies for vehicles and, more particularly, to a lightweight, economical vehicle window assembly which is installed as a unit on a vehicle with any fasteners being concealed from view from the exterior, while providing decorative trim and sealing functions as part of the unit.
It has been common in vehicle manufacturing procedures to use a piecemeal assembly operation to install a window. Thus, a bead of sealant or the like is applied around the frame of a window, a pane of glass is pressed against the sealant and several clips or fasteners are secured around the glass edge to the surrounding frame to hold the glass in place. Thereafter, decorative covers or frames are placed around the frame or glass edge to dress the edge and cover the fastening area. As will be appreciated, such assembly procedures are time-consuming and expensive. They may also be prone to sealing problems should the bead of sealant not be applied properly or the fasteners be loose or otherwise improperly installed.
More recently, unitary window assemblies have been devised for installation directly from the exterior of a vehicle. Such assemblies, like that shown in U.S. Pat. No. 4,072,340, have included a pane of glass, an adjacent frame, and a casing or gasket of molded material, such as polyvinyl chloride, extending between the frame and the peripheral edge of the window which holds the pane and frame together. Fasteners are provided at spaced locations along the frame such that the entire assembly can be guided into location over an opening in a vehicle body as a unit with the fasteners extending through apertures provided in the body and secured in a single operation from the interior of the vehicle body.
Alternatively, window assemblies, such as that shown in U.S. Pat. No. 4,139,234, have included a molded casing or gasket around the edge of a pane of glass with fasteners molded in and projecting from the casing or gasket for attachment purposes.
Such prior unitary window assemblies have recently come under close scrutiny because of increased concern over weight reduction and fuel efficiency in automobiles and other vehicles. The relatively heavy frame, typically cast from zinc or other metal and/or the molded gasket or casing for securing the frame to the window provide significant weight in each window assembly. In addition, as in the structure of U.S. Pat. No. 4,072,340, the decorative frame, which requires the inclusion of fastening means therealong to secure the entire assembly in a vehicle, requires expensive casing techniques making the frame members relatively expensive.
With the focus on weight reduction and economics in designing new vehicles, it was desired that window assemblies be lighter in weight and less expensive, yet retain rigidity, strength and structural integrity. The present invention was conceived as a solution for the above problems while maintaining the strength, decorative trim function, sealing function and desirable fastening characteristics of previously known unitary or modular window assemblies.